Why Do Speaker Drivers Blow Out?
Speaker drivers blowing out during use is a major problem in Sound Reinforcement systems and can waste no small amount of repair budget.
Heat Buildup
When too much heat accumulates, the speaker driver can burn and be damaged. This can happen for several reasons — for example, the amplifier has a higher output than the speaker driver's RMS wattage, causing heat to build up. For instance, the speaker driver has an RMS rating of 600 watts, but the amplifier delivers an output of 1,200 watts RMS, exceeding the driver's RMS rating.
Over Excursion
Over Excursion is damage caused by tearing in the speaker driver, because the amplifier's Peak wattage exceeds the driver's Peak wattage beyond what it can handle — for example, the speaker driver has a Peak rating of 900 watts, but the amplifier drives at full power of 1,700 watts.
Over-Adjusting the Equalizer
Adjusting the Equalizer in certain frequency bands in ways that don't suit the speaker's characteristics — for example, a low-frequency speaker such as a Subwoofer — can blow the driver if the tone is boosted with very high frequencies. Therefore, before adjusting the Equalizer, examine it carefully and thoroughly, or consult an expert.
These three cases that cause speakers to blow or be damaged are only the basics; there are still other cases that can cause a speaker to blow or be damaged, such as the environment of the usage area or the speaker's age. You can use this information to solve problems — from choosing equipment such as amplifiers and speakers, to configuring your current system to work efficiently — and it also helps reduce maintenance costs.
Frequently asked questions
What causes a speaker driver to blow out?
Three basic cases: heat buildup until the driver burns; over excursion, which tears the driver; and over-adjusting the equalizer in frequency bands that don't suit the speaker. Other factors include the environment where it is used and the speaker's age.
Can an over-powered amplifier damage speakers?
Yes. If the amplifier's output exceeds the driver's RMS rating, heat builds up — for example, a driver rated 600 watts RMS with an amplifier delivering 1,200 watts RMS. Over excursion occurs when the amplifier's peak wattage exceeds what the driver can handle, such as a 900-watt peak driver with an amplifier driving at 1,700 watts.
Can adjusting the equalizer damage a speaker?
Yes, if you adjust bands that don't suit the speaker's characteristics — for example, boosting very high frequencies on a subwoofer designed for low frequencies can blow the driver. Examine carefully before adjusting, or consult an expert.